The following example demonstrates interface implementation. 
In this example, the interface IPoint contains the property declaration, 
which is responsible for setting and getting the values of the fields. 
The class Point contains the property implementation.

// keyword_interface_2.cs
// Interface implementation
using System;
interface IPoint
{
   // Property signatures:
   int x
   {
      get;
      set;
   }

   int y
   {
      get;
      set;
   }
}

class Point : IPoint
{
   // Fields:
   private int _x;
   private int _y;

   // Constructor:
   public Point(int x, int y)
   {
      _x = x;
      _y = y;
   }

   // Property implementation:
   public int x
   {
      get
      {
         return _x;
      }

      set
      {
         _x = value;
      }
   }

   public int y
   {
      get
      {
         return _y;
      }
      set
      {
         _y = value;
      }
   }
}

class MainClass
{
   static void PrintPoint(IPoint p)
   {
      Console.WriteLine("x={0}, y={1}", p.x, p.y);
   }

   static void Main()
   {
      Point p = new Point(2, 3);
      Console.Write("My Point: ");
      PrintPoint(p);
   }
}

output:
My Point: x=2, y=3


----------
interface IEmployee
{
    string Name
    {
        get;
        set;
    }

    int Counter
    {
        get;
    }
}

public class Employee : IEmployee
{
    public static int numberOfEmployees;

    private string name;
    public string Name  // read-write instance property
    {
        get
        {
            return name;
        }
        set
        {
            name = value;
        }
    }

    private int counter;
    public int Counter  // read-only instance property
    {
        get
        {
            return counter;
        }
    }

    public Employee()  // constructor
    {
        counter = ++counter + numberOfEmployees;
    }
}

class TestEmployee
{
    static void Main()
    {
        System.Console.Write("Enter number of employees: ");
        Employee.numberOfEmployees = int.Parse(System.Console.ReadLine());

        Employee e1 = new Employee();
        System.Console.Write("Enter the name of the new employee: ");
        e1.Name = System.Console.ReadLine();

        System.Console.WriteLine("The employee information:");
        System.Console.WriteLine("Employee number: {0}", e1.Counter);
        System.Console.WriteLine("Employee name: {0}", e1.Name);
    }
}


output
Enter number of employees: 210 
Enter the name of the new employee: Hazem Abolrous 
The employee information: 
Employee number: 211 
Employee name: Hazem Abolrous